Ladder construction



Sept. 12, 1933. c. A. RICH 1,926,885

LADDER CONSTRUCTION Filed Dec. 1, 1952 I I I 7 5 10- 2 Patented Sept. 12, 1933 LADDER CONSTRUCTION Chester A. Rich, Cincinnati, Ohio Application December 1, 1932. Serial No. 645,247

8 Claims.

This 'invention relates to improvements in ladder construction, whereby the cost of production of re-enforced runged ladders is reduced to a minimum.

Besides reduction of manufacturing cost, other objects of the invention are, to provide an eiiective yet inexpensive means for precluding looseness and rotational movement of the rungs relative to the side rails or risers of the ladder;. to provide a double rung-locking key which will maintain its locking function even though the rung truss, which is integral with the key means, should insome manner become broken; and to dispense with the. use of screw threaded truss means, which in the majority of structures become loosened and are permitted to remain in the loosened condition.

The foregoing andother objectsare attained 'by the means described herein and disclosed in the accompanying drawing, in which: 7

Fig. l is a side elevational view of a embodying the invention.

Fig. 2 is a front elevational View of the ladder of Fig. 1, part thereof being shown in ores..- section.

Fig. 3 is an enlarged end view of a re-enforced rung embodying the invention.

In the'manuiacture of trussed or reeniorced rung'ladders, the practice heretofore has been to provide truss members which extended transversely of and through the side rails, beneath the rungs, and which truss members were provided ladder with screw threaded ends adapt d to receive nuts.

or the like for drawing the truss members to a tensioned condition. Certain improvements upon such re-enforced structures proposed passage of the truss member through or partly through the rungs for the purpose of precluding rotation of the rungs relative to the side rails or risers, but said proposals imposed the necessity of very accurately fitting the parts, and performing costly machine operations, in addition to threading the ends of the truss members and applying nuts thereto. The present invention has as one of its objects the elimination of much of the costly machine work and accurate fitting of parts that would be necessary in the manufacture of the heretofore proposed constructions.

' In accordance with the present invention, the truss member 5 is constituted of a single length i heavy wire stock, the opposite ends 6 of which are not threaded in the customary manner. The rung 7 preferably has its opposite ends 8 turned to a smaller diameter than the intermediate or step portion thereof, to provide shoulders 9 which abut the inner faces 10 of the side rails or risers 12 when the reduced ends of the rung are seated in the opposed perforations or bores 13 of the rails. The reduced ends of the rungs preferably, though not necessarily, extend entirely through the side rails, as illustrated in the drawing.

Prior to fitting of the rung into position between the risers, the rung has each of reduced ends drilled or otherwise provided with a passageway, asindicated at 14., for reception of the opposite ends of the wire truss member, which ends arethereafter turned in the direction of the shoulders 9 so as to lie flatly, or substantially so, upon the uppermost region of the reduced ends, and in substantial parallelism with the long-i tudinal axis of the rung. The ends 6 thereby are formed to function as keys which preclude rotation of the rung ends in their supports. A second pair of keys 15 are provided by forcing intermediate sections of the truss membcrinto contacting relationship with the lower curved surfaces of the reduced rung ends, as shown.

hat portion of the truss member which is be tween the rails 12 preferably lies in close proximity with the under surface of the rung, in parallelism therewith.

To assemble the ladder, the pro-formed rungs initially are placed between the rails so as to co incide with their respective openings 13, after which pressure is applied to the side rails for forcing the rungs into the ultimate seated rela tionship shown. During the said compressing of the rails, the key portions 6 and 15 are forced into place, making their own grooves or costs: in the material of the side rails. After the pa'ts are thus connected in the proper relationship, one or more nails or screws 17 may be driven into the side rails and through the reduced ends of the rungs in order to hold the side rails in properly spaced relationship. The bores or drill holes 14 are located suficiently close to the ends of the rung to permit driving of the fasteners 17 throughsubstantiallythe mid-portion of each reduced end.

In addition to the advantages above set forth, it is to be noted that the diameter of the rung ends need not be gauged to closely approximate the diameter of the bores or openings 13, because the two pairs of key members 6 and 15 quite effectually insure a tight connection between the rungs and the side rails. The absence of expensive constituent parts and costly machine operations in the manufacture of the improved devices, should readily be apparent.

It is to be understood that various modifications and changes in structural details of the device may be made, within the scope of the appended claims, without departing from the spirit of the invention.

What is claimed is:

l. A ladder construction comprising in combination a side rail having formed therein a transversely disposed aperture, a rung having a step portion and an end for reception by the aperture of the side rail, said end having a passageway formed therein extending transversely of the 1ongitudinal axis of the rung, and a truss member having a portion lying adjacent to the step portion of the rung, one end of the truss member being received by the passageway and bent upon itself to form a pair of extending keys'disposed at opposite sides of the rung end and adapted to be embedded in the material of the side rail upon insertion of the rung end into the aperture of said side rail.

2. A ladder construction comprising in combination a side rail having formed therein a transversely disposed aperture, a rung having a step portion and an end for reception by the aperture of the side rail, said end having a passageway formed therein extending transversely of the longitudinal axis of the rung, and a truss member havin a portion lying adjacent to the step portion of the rung, one end of the truss member being received by the passageway and bent to form a key whose longitudinal axis lies in substantial parallelism with the longitudinal axis of the rung.

3. A ladder construction comprising in combination a side rail having formed therein a transversely disposed aperture, a rung having a step portion and a reduced end providing a shoulder, the reduced end having a passageway formed therein extending transversely of the longitudinal axis of the rung, and a truss member extending along the rung, said truss member having an end extended through the passageway for a distance sufiicient for turning of said end toward the shoulder and thereby providing a key on the reduced end of the rung, the reduced rung end and the key being received by the aperture of the side rail.

4. A ladder construction comprising in combination a side rail having formed therein a transversely disposed aperture, a rung having a step portion and an end. for reception by the aperture of the side rail, the said end having a passagaway formed therein extending transversely of the longitudinal axis of the rung, and a truss member extending along the rung, said truss member having an end extended through the passageway for a distance suiiicient for the turning ofsaid end in the direction of the step portion of the rung, the turned end of the truss member and the end of the rung being received by the aperture of the side rail.

5. A ladder construction comprising in combination a side rail having formed therein a.

transversely disposed aperture, a rung having a step portion and an end for reception by the aperture of the side rail, the said end being of a diameter such that it may freely enter the side rail aperture, and having a passageway formed therein extending transversely of the longitudinal axis of the rung, and a truss member extending along the rung said truss member having an end extended through the passage way for a distance sufiicient for the turning of said end in the direction of the step portion of the rung, the turned end of the truss member and the end of the rung being received by the aperture of the side rail.

6. A ladder construction comprising in combination a pair of spaced side rails each of which has formed therein a transverse aperture, a rung having a step portion and ends for reception by the apertures of the side rails, said ends each having a passageway formed therein extending transversely of the longitudinal axis of the rung,

and a truss member having a portion extending along the full length of the step portion and having opposite ends each of which is received by the passageway and bent to provide a key disposed exteriorly of the passageway and lying substantially along the surface of the end section of the rung, the exposed portion of the keys being thereby adapted to sink themselves into the material of the side rails when the ends of the rungs are forced into the apertures of the side rails, and means for maintaining the side rails in the spaced relationship.

'7. A joint comprising a pair of members one of which is apertured and the other of which has an end shaped to fit within the aperture of the first member, the second mentioned member having a transverse passageway formed in its said end, and a wire disposed within said passageway said Wire being bent in substantial U-shape with the legs of the U lying exteriorly of the passageway and substantially upon said end, the legs functioning as keys capable of sinking themselves into the material of the apertured member when the end of the second member is forced into the aperture of the first member.

8. A joint comprising a pair of members one of which is apertured and the other of which has an end shaped to fit Within the aperture of the first member, the second mentioned member having a transverse passageway formed in its said end, and a wire having a portion thereof resting in the passageway and another portion thereof bent angularly to lie exteriorly of the passageway and substantially upon said end, the exteriorly disposed portion functioning as a key capable of sinking itself into the material of the apertured member when the end of the second member is forced into the aperture of the first member.

CHESTER A. RICH. 

